Fuel supply systems



July 27, 1965 w. A. GARTLAND 3, 9

FUEL SUPPLY SYSTEMS Filed May 28, 1962 2 Sheets-Sheet l FUEL ' TA NKF/Gl 32 F/GZ FUEL TANK

W/L L /AM A. GA RTL AND July 27, 1965 w. A. GARTLAND FUEL SUPPLY SYSTEMS2 Sheets-Sheet 2 .Filed May 28, 1962 W/LL/AM A. 6/11? TLAND INVEN? K m Bi i QM f ATTOZRNEYS United States Patent ice 3,196,926 FUEL SUPPLYSYSTEMS William A. Gartland, Dearborn, Mich, assignor to Ford MotorCompany, Dearborn, Mich, a corporation of Delaware Filed May 28, 1962,Ser. No. 198,180 4 Claims. (Cl. 158-36.3)

This invention relates to fuel supply systems for internal combus-ionengines, and more particularly to fuel supply systems that insure asupply of low temperature fuel to the fuel introducing device of theengine at all times.

The high volitility that makes gasoline a desirable fuel for internalcombustion engines also creates several problems with its use as a fuel.The low boiling point of gasoline frequently results in a conditionknown as vapor lock. Vapor lock occurs when gasoline vaporizes in thefuel lines, fuel pump or fuel bowl of the engines charge forming device.This problem is particularly acute in motor vehicles where the engine isconfined within a vehicle body.

The rate of air flow through the engine compartment when the vehicle ismoving normally maintains a temperature low enough to prevent vaporlock. Under certain conditions, however, the engine compartmenttemperature becomes excessive and, unless some means is provided ofcooling the fuel, vapor lock will occur. Engine compartment temperaturemay become excessive during extended idle periods or under a conditionknown in the art as soak. Soak periods are times when a thoroughlyheated engine is shut off and permitted to radiate its heat into theengine compartment.

It is, therefore, the principal object of this invention to provide afuel feed system for an internal combustion engine that maintains a lowfuel temperature throughout the system.

It is a further object of this invention to provide a proportioningmeans for a fuel feed system that permits excess quantities of fuel tobe pumped by the fuel pump and returned to the fuel tank to maintain alow fuel temperature in the system.

Heretofore the fuel pump of the fuel supply system has been a separateelement of the system. Because the fuel pump is a separate element inconventional systems and must be interposed in the fuel supply circuit,the use of at least two fluid tight fittings is required. If the fuelpump could be formed integrally with one of the other elements of thesystem, preferably the charge forming device, the use of additionalfittings could be obviated insuring a leak proof system.

It is, therefore, a still further object of this invention to provide acharge forming device incorporating an inegral fuel pump.

A fuel supply system for an internal combustion engine embodying thisinvention includes a fuel tank and a fuel introducing device for theengine. A fuel pump adapted to pump a quantity of fuel exceeding therequirements of the engine for its normal operation has its input sideconnected by conduit means with the fuel tank. Second conduit meansinterconnect the output side of the fuel pump with the charge formingdevice. Proportioning means are interposed in the second conduit meansfor diverting the excess portion of the fuel flowing in the secondconduit means from the fuel introducing device back to the fuel tank.The provision of excess fuel flow insures that the temperature of thefuel in the system will approximate the temperature of the fuel in thefuel tank.

In an embodiment of this invention a cooling fuel jacket encircles thefuel bowl of a charge forming device. The excess quantity of fuel pumpedis diverted to the cool- 3,196,926 Patented July 27, 1965 ing fueljacket to draw the heat from the fuel in the fuel bowl.

In another embodiment of the invention bypass means are interposedbetween the output side of the fuel pump and the fuel introducingdevice. The bypass means includes proportioning means that divert theexcess portion of .the fuel pumped by the fuel pump to a fuel receivingchamber positioned externally of the fuel introducing device. The excessfuel pumped to the fuel receiving chamber flows from outlet means formedin the fuel receiving chamber through a conduit back to the fuel tank.

In a still further embodiment of the invention a charge forming devicehaving an induction passage and a fuel bowl that discharges fuel intothe induction passage is provided. A fuel pump is contained within thecharge forming device and pumps fuel into the fuel bowl through conduitmeans extending from the discharged side of the fuel pump.

Further objects and advantages of this invention will become moreapparent as this description proceeds particularly when considered inconjunction wtih the accompanying drawings, wherein:

FIGURE 1 is a top plan view illustrating schematically the fuel supplysystem of an internal combustion engine incorporating an embodiment ofthis invention with portions shown in section and other portions brokenaway.

FIGURE 2 is a cross sectional view taken along line 22 of FIGURE 1.

FIGURE 3 is a cross sectional view taken along line 33 of FIGURE 1.

FIGURE 4 is a side elevational view showing schematically anotherembodiment of the invention with portions in section.

Referring now in detail to the fuel supply systems illustrated in thedrawings and in particular to the embodiment shown in FIGURES 1-3, aportion of a charge forming device is indicated generally at 11. Thecharge forming device 11 has a body portion 12 formed to provide a fuelbowl 13. A float 14 is pivotally supported within the fuel bowl 13 uponthe pin 15. A tang 16 formed upon the float 14 controls the position ofa needle valve 17 interposed in the inlet fitting 18 threaded into thebody portion 12. The needle valve 17 seats upon a shoulder 19 formedaround the internal conduit 21 of the inlet fitting 18 to control theflow of fuel into the fuel bowl 13 and maintain a normal fuel leveltherein. Fuel may flow from the fuel bowl 13 and be discharged intoinduction passages 22 formed in the body portion 12 by suitable nozzles,flow controlling means and conduits (not shown).

Formed integrally within the body portion 12 is a cooling fuel jacket 23that is positioned around three sides of the fuel bowl 13. The coolingfuel jacket 23 extends for substantially the same height as the fuelbowl 13. A plurality of metered openings 24 are formed in the portion ofthe inlet fitting 18 that extends through the cool ing fuel jacket 23(FIGURES 1 and 2). Because of the metered openings 24 and the needlevalve 17, the inlet fitting 18 may function as proportioning means todirect a portion of the fuel flowing therethrough to the fuel bowl 13and divert a portion of the fuel to the cooling fuel jacket 23.

Fuel may flow from the fuel tank, indicated schematically in FIGURES 1and 2, through a conduit 25 to a fuel pump assembly indicated generallyat 26. In the embodiment of the invention illustrated in FIGURES 1-3,the fuel pump assembly 26 is contained within the charge forming device11. To this end the body portion 12 is formed to provide a cavity 27.The fuel pump illustrated is of the intermeshing external tooth geartype and comprises a driven gear 28 and an idler gear 29 positionedwithin the cavity 27. A cover plate 31 extends across the externalopening of the cavity 27 and a gasket 32 is provided around theperiphery of the cover plate 31. Suitable means (not shown) are providedfor securing the cover plate 31 and gasket 32 to the body portion 12 toform a fluid tight enclosure.

The idler gear 29 is rotatably supported within the cavity 27 upon astub shaft 33 that is affixed to the cover plate 31. The gear 28 isaffixed to a driving shaft 34 rotatably supported by the cover plate 31.The driving shaft 34 extends from within the charge forming device andis formed at its end with a male portion 35 of a socket assembly. Themale portion 35 of the socket assembly may be secured to any suitableelement to provide motive power for the fuel pump assembly 26. Forexample, the driving shaft 34 may extend into the internal portion ofthe engine to be driven by its camshaft. The male socket portion 35 canbe received in a female socket portion formed in a worm gear that mesheswith a worm wheel aflixed to the camshaft.

A fluid inlet conduit 36 is formed in the cover plate 31, fuel pumpassembly 26 and opens into the cavity 27. A fitting 37 is formed on thedischarge end of the inlet conduit 25 and is threaded into the coverplate 31 to allow fuel to flow from the fuel tank into the cavity.

An outlet port 38 is formed in the body portion 12 and extends from thecavity 27 to an elongated fluid receiving cavity 39 formed within thebody portion 12. The inlet fitting 18 passes through the cavity 39 and,within the cavity 39, is formed a plurality of inlet openings 41. Fuelmay flow from the cavity 39 into the inlet fitting 18 through the inletopenings 41 and be discharged into the cooling fuel jacket 23 and thefuel bowl 13.

The operation of the embodiment shown in FIGURES 1-3 is as follows, fuelis drawn by the fuel pump assembly 26 from the fuel tank through conduit25. The fuel pump assembly 26 is adapted to pump a quantity of fuel inexcess of that required by the engine for its normal operation. Fuel isdischarged from the pump 26 through the outlet port 38 into the cavity39. From the cavity 39 fuel flows through the inlet openings 41 into theinlet fitting 18 and through its internal conduit 21. As the needlevalve 17 is opened and closed by the float 14, fuel is discharged intothe fuel bond 13. The excess quantity of the fuel flowing is shuntedthrough the metered openings 24 in the inlet fitting 13 to the coolingfuel jacket 23. The excess fuel flowing through the cooling fuel jacket23 surrounds the fuel bowl 13 and provides insulation and coolingtherefor.

One or more outlet openings 42 are provided in the cooling fuel jacket23 at the upper portion thereof. Outlet fittings 43 are threaded intothe outlet openings 42 and connected by outlet conduits 44 to the fueltank. The excess fuel flowing into the cooling fuel jacket 23 will berecirculated to the fuel tank through the conduits 44. Because a majorportion of the fuel circulating has been returned to the fuel tank, thetemperature of the fuel in the system will approximate the temperatureof the fuel in the fuel tank. A low fuel temperature throughout thesystem is thus maintained to preclude the possibility of vapor lock.

If desired the internal fuel pump assembly 26 shown in the embodiment inFIGURES 1-3 may be replaced by a conventional externally positioned fuelpump. The fuel pump should be, however, adapted to pump a quantity offuel in excess of that required by the engine for its normal operation.The outlet side of the fuel pump may be directly connected to the inletfitting 18 positioned in the carburetor body 12 'by removing a plug 45positioned therein.

Referring now to the embodiment shown in FIGURE 4, a fuel supply systemcomprising a fuel tank, fuel pump, fuel receiving chamber 61 and chargeforming device 62 are shown schematically. The fuel pump is adapted tosupply a quantity of fuel that exceeds the normal amount the chargeforming device 62 furnishes to meet the requireme ts the g Fuel flowsfrom the fuel tank to the inlet side of the fuel pump through a conduit63. The discharged side of the fuel pump is connected to the chargeforming device 62 by a conduit indicated generally at 64.

The conduit 64 includes a tube 65 having an outlet coupling 66 that isthreaded into a fitting 67 upon the charge forming device 62. A fitting68 is formed at the inlet end of the tube 65 to permit connection with aflexible tubing that extends from the discharged side of the fuel pump.The fuel receiving chamber 61 comprises a cylindrical body portionclosed at one end by a cap 69 at the other end by a head 71 formedintegrally therewith. The tube 65 passes through an opening 72 formed inthe head 71 and an opening 73 formed in the cap 69. Within the interiorof the fuel receiving chamber 61, the tube 65 is formed with a pluralityof metered openings 74. The openings 74 permit fuel to flow from thetube 65 into the fuel receiving chamber 61. An outlet port 75 is formedin the head 71 of the fuel receiving chamber 61 and has received thereinan outlet pipe 76. The pipe is adapted to be connected to the fuel tankby a return conduit 77.

As has been noted the fuel pump is adapted to pump a quantity of fuelthat exceeds the normal requirements of the engine. The excess fuelpumped into the tube 65 will be discharged through the metered openings74 into the fuel receiving chamber 61. The excess fuel will then bereturned through the conduit 77 to the fuel tank. By causing an excessquantity of fuel to flow through the system and by returning the excessfuel to the fuel tank, the temperature of the fuel circulating willapproximate the temperature of the fuel in the tank. In this way aconstant supply of low temperature fuel is provided to the chargeforming device 62.

Although the fuel receiving chamber 61 and metered tube 65 are shown inconjunction with a specific type of charge forming device, it is to beunderstood that the invention may be practiced with a fuel injectionnozzle or various other forms of fuel introducing devices for an engine.The excess quantity of fuel that is recirculated will provide a coolfuel supply for whatever form of fuel inducing device employed. Thiswill preclude the possibility of vapor lock in the fuel supply system.

It is to be understood that the invention is not limited to theembodiments shown and described, but that other changes andmodifications may be made without departing from the spirit and scope ofthe invention, as defined by the appended claims.

I claim:

1. A fuel supply system for an internal combustion engine comprising afuel tank, a charge forming device having a fuel bowl, means formaintaining a uniform fuel level in said fuel bowl, a cooling fueljacket around said fuel bowl in contact with a substantial area of thewall defining said fuel bowl, a fuel pump adapted to pump a quantity offuel in excess of the requirements of the engine for its normaloperation, first conduit means connecting the input side of said fuelpump with said fuel tank, means delivering fuel from the output side ofsaid fuel pump to said fuel bowl and said cooling fuel jacket, andsecond conduit means for returning to said fuel tank the excess fuelpumped.

2. A fuel supply system for an internal combustion engine comprising afuel tank, a charge forming device having a fuel bowl, means formaintaining a uniform fuel level in said fuel bowl, a cooling fueljacket around said fuel bowl in contact with a substantial portion ofthe wall defining said fuel bowl, a fuel pump adapted to pump a quantityof fuel in excess of the requirements of the engine for its normaloperation, first conduit means connecting the input side of said fuelpump with said fuel tank, means delivering fuel from the output side ofsaid fuel pump to said fuel bowl and said cooling fuel jacket, meansdiverting the excess portion of the fuel pumped by said fuel pump tosaid cooling fuel jacket, and second 5 conduit means interconnectingsaid cooling fuel jacket with said fuel tank for returning to said fueltank the excess fuel pumped.

3. A fuel supply system for an internal combustion engine comprising afuel tank, a charge forming device having a body portion forming a fuelbowl, a cooling fuel jacket formed around said fuel bowl in said bodyportion, said body portion having an upstanding Wall separating saidcooling fuel jacket from said fuel bowl, a fuel inlet for said fuel bowland said cooling fuel jacket, said fuel inlet comprising an inletfitting having an axially extending fuel passage, a fuel inlet sideformed in said inlet fitting, said inlet fitting being received in saidbody and passing through said Wall, said inlet fitting further having atleast one radial opening into said cooling jacket, a fuel pump adaptedto pump a quantity of fuel in excess of the requirements of the enginefor its normal operation, first conduit means connecting the input sideof said fuel pump with said fuel tank, second conduit meansinterconnecting the output side of said fuel pump With said inlet sideof said inlet fitting, a fuel outlet in said cooling 6 fuel jacket, andthird conduit means interconnecting said fuel outlet with said fueltank.

4. A fuel supply system as defined by claim 3 wherein a float controlledvalve is positioned at the opening of said inlet fitting into said fuelbowl to control the level of fuel in said fuel bowl.

References Cited hy the Examiner UNITED STATES PATENTS 1,196,552 8/16 LaPorte.

1,881,860 10/32 Muzzy.

2,254,850 9/41 Mallory 158-364 2,409,965 10/46 Udale 158-363 2,414,3221/47 Mock 261-361 2,454,974 11/48 Mennesson 26136.l 2,795,269 6/57 Witte158-36.4 X 2,905,455 9/59 Eberhardt 26 1-3 6.1 2,963,013 12/60 Fisher.

3,026,862 3/62 Fisher.

JAMES W. WESTHAVER, Primary Examiner FREDERICK KETTERER, Examiner.

1. A FUEL SUPPLY SYSTEM FOR AN INTERNAL COMBUSTION ENGINE COMPRISING AFUEL TANK, A CHARGE FORMING DEVICE HAVING A FUEL BOWL, MEANS FORMAINTAINING A UNIFORM FUEL LEVEL IN SAID FUEL BOWL, A COOLING FUELJACKET AROUND SAID FUEL BOWL IN CONTACT WITH A SUBSTANTIAL AREA OF THEWALL DEFINING SAID FUEL BOWL, A FUEL PUMP ADAPTED TO PUMP A QUANTITY OFFUEL IN EXCESS OF THE REQUIREMENTS OF THE ENGINE FOR ITS NORMALOPERATION, FIRST CONDUIT MEANS CONNECTING THE INPUT SIDE OF SAID FUELPUMP WITH SAID FUEL TANK, MEANS DELIVERING FUEL FROM THE OUTPUT SIDE OFSAID FUEL PUMP TO SAID FUEL BOWL AND SAID COOLING FUEL JACKET, ANDSECOND CONDUIT MEANS FOR RETURNING TO SAID FUEL TANK THE EXCESS FUELPUMPED.